1. Field of the Invention
The field of the present invention is helmets of a type having a shield and used primarily by an occupant on a snowmobile, a motorcycle or the like, and particularly, improvements in helmets of a type having its shield attached at left and right ends thereof to a cap body through a pivotal mounting means for opening and closing a window opening formed in a front surface of the cap body.
2. Description of the Prior Art
It is already known that when such a helmet is in use with the shield fully closed, travel wind produced by travelling of a vehicle is directed to an inner surface of the shield in order to prevent a cloud of the inner surface of the shield which may occur due to expiration of a user (for example, see Japanese Patent Application Laid-open No. 159507/88).
However, such a helmet suffers from a problem that during stoppage of the vehicle where there is no travel wind, a cloud is liable to be produced on the inner surface of the shield, and in use in a cold district, a cloud may be produced on the inner surface of the shied due to a large difference in temperature between the shield cooled by the outside air and the inside of the cap body.